Alpha-1 adrenergic signaling in a cardiac murine atrial myocyte (HL-1) cell line

作者：McWhinney CD^*; Hansen C; Robishaw JD

来源：Molecular and Cellular Biochemistry, 2000, 214(1-2): 111-119.

DOI：10.1023/A:1007129723949

• alpha-1 adrenergic
• receptor subtypes
• atrial cells
• atrial natriuretic factor
• ANF
• HL-1 cells
• myocytes
• cell signaling

Activation of alpha-1 adrenergic receptors in the heart has been shown to result in increased contractile activity, cardiac fetal gene re-expression, and myocyte hypertrophy. Three alpha-1 adrenergic receptors have been identified through molecular cloning. Due to the limited selectivities of the currently available alpha-1 adrenergic receptor antagonists, the signaling pathways activated by specific subtypes in the heart remain unresolved. To resolve this dilemma, we have used a molecular approach to identify the signaling pathways and downstream genes that are engaged in response to activation of individual alpha-1 adrenergic subtypes in cardiac cells. We have transfected constitutively active alpha-1 adrenergic receptors (alpha (1a)-S-290/293-AR [1] or the alpha (1b)-S-288/294-AR [2]) subtypes into the cardiac murine myocyte cell line (HL-1) and studied the signal transduction pathway(s) and cardiac gene(s) activated by them. In this study, we demonstrate that the alpha (1a)-S-290/293-AR [1] subtype preferentially couples to cardiac-specific atrial natriuretic factor (ANF) gene expression, while the alpha (1b)-S-288/294-AR preferentially couples to activation of mitogen-activated protein kinase (MAPK), Ets-like transcription factor-1 (Elk1) and serum response element (SRE) signaling pathways. Endogenous alpha-1 adrenergic receptors are expressed, and stimulate phosphatidylinositol-hydrolysis upon activation with the alpha-1 agonist, phenylephrine.

• 出版日期2000-11